<!doctype html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport"
          content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
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    <title>Document</title>
</head>
<body>
    <h1>这是大标题</h1>
    <button onclick="runAppFun()">按钮</button>
    <script>
        function changeText() {
            document.querySelector('h1').innerText = '你好帅！！！'
        }

        function runAppFun() {
            objName.objKey()
        }
    </script>

</body>
</html>